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-- --
-- --
-- L I B . X R E F --
-- --
-- S p e c --
-- --
-- Copyright (C) 1998-2003, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, USA. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
-- This package contains for collecting and outputting cross-reference
-- information.
with Einfo; use Einfo;
with Types; use Types;
package Lib.Xref is
-- Format of Cross-Reference Information in ALI File --
-- Cross-reference sections follow the dependency section (D lines) in
-- an ALI file, so that they need not be read by gnatbind, gnatmake etc.
-- A cross reference section has a header of the form
-- X dependency-number filename
-- This header precedes xref information (entities/references from
-- the unit, identified by dependency number and file name. The
-- dependency number is the index into the generated D lines and
-- is ones origin (i.e. 2 = reference to second generated D line).
-- Note that the filename here will reflect the original name if
-- a Source_Reference pragma was encountered (since all line number
-- references will be with respect to the original file).
-- The lines following the header look like
-- line type col level entity renameref typeref ref ref ref
-- line is the line number of the referenced entity. The name of
-- the entity starts in column col. Columns are numbered from one,
-- and if horizontal tab characters are present, the column number
-- is computed assuming standard 1,9,17,.. tab stops. For example,
-- if the entity is the first token on the line, and is preceded
-- by space-HT-space, then the column would be column 10.
-- type is a single letter identifying the type of the entity.
-- See next section (Cross-Reference Entity Identifiers) for a
-- full list of the characters used).
-- col is the column number of the referenced entity
-- level is a single character that separates the col and
-- entity fields. It is an asterisk for a top level library
-- entity that is publicly visible, as well for an entity declared
-- in the visible part of a generic package, and space otherwise.
-- entity is the name of the referenced entity, with casing in
-- the canical casing for the source file where it is defined.
-- renameref provides information on renaming. If the entity is
-- a package, object or overloadable entity which is declared by
-- a renaming declaration, and the renaming refers to an entity
-- with a simple identifier or expanded name, then renameref has
-- the form:
-- =line:col
-- Here line:col give the reference to the identifier that
-- appears in the renaming declaration. Note that we never need
-- a file entry, since this identifier is always in the current
-- file in which the entity is declared. Currently, renameref
-- appears only for the simple renaming case. If the renaming
-- reference is a complex expressions, then renameref is omitted.
-- Here line/col give line/column as defined above.
-- typeref is the reference for a related type. This part is
-- optional. It is present for the following cases:
-- derived types (points to the parent type) LR=<>
-- access types (points to designated type) LR=()
-- array types (points to component type) LR=()
-- subtypes (points to ancestor type) LR={}
-- functions (points to result type) LR={}
-- enumeration literals (points to enum type) LR={}
-- objects and components (points to type) LR={}
-- In the above list LR shows the brackets used in the output,
-- which has one of the two following forms:
-- L file | line type col R user entity
-- L name-in-lower-case R standard entity
-- For the form for a user entity, file is the dependency number
-- of the file containing the declaration of the related type.
-- This number and the following vertical bar are omitted if the
-- relevant type is defined in the same file as the current entity.
-- The line, type, col are defined as previously described, and
-- specify the location of the relevant type declaration in the
-- referenced file. For the standard entity form, the name between
-- the brackets is the normal name of the entity in lower case.
-- There may be zero or more ref entries on each line
-- file | line type col [...]
-- file is the dependency number of the file with the reference.
-- It and the following vertical bar are omitted if the file is
-- the same as the previous ref, and the refs for the current
-- file are first (and do not need a bar).
-- line is the line number of the reference
-- col is the column number of the reference, as defined above.
-- type is one of
-- b = body entity
-- c = completion of private or incomplete type
-- d = discriminant of type
-- e = end of spec
-- H = abstract type
-- i = implicit reference
-- k = implicit reference to parent unit in child unit
-- l = label on END line
-- m = modification
-- p = primitive operation
-- P = overriding primitive operation
-- r = reference
-- t = end of body
-- w = WITH line
-- x = type extension
-- z = generic formal parameter
-- > = subprogram IN parameter
-- = = subprogram IN OUT parameter
-- < = subprogram OUT parameter
-- > = subprogram ACCESS parameter
-- b is used for spec entities that are repeated in a body,
-- including the unit (subprogram, package, task, protected
-- body, protected entry) name itself, and in the case of a
-- subprogram, the formals. This letter is also used for the
-- occurrence of entry names in accept statements. Such entities
-- are not considered to be definitions for cross-referencing
-- purposes, but rather are considered to be references to the
-- corresponding spec entities, marked with this special type.
-- c is similar to b but is used to mark the completion of a
-- private or incomplete type. As with b, the completion is not
-- regarded as a separate definition, but rather a reference to
-- the initial declaration, marked with this special type.
-- d is used to identify a discriminant of a type. If this is
-- an incomplete or private type with discriminants, the entry
-- denotes the occurrence of the discriminant in the partial view
-- which is also the point of definition of the discriminant.
-- The occurrence of the same discriminant in the full view is
-- a regular reference to it.
-- e is used to identify the end of a construct in the following
-- cases:
-- Block Statement end [block_IDENTIFIER];
-- Loop Statement end loop [loop_IDENTIFIER];
-- Package Specification end [[PARENT_UNIT_NAME .] IDENTIFIER];
-- Task Definition end [task_IDENTIFIER];
-- Protected Definition end [protected_IDENTIFIER];
-- Record Definition end record;
-- Enumeration Definition );
-- Note that 'e' entries are special in that they appear even
-- in referencing units (normally xref entries appear only
-- for references in the extended main source unit (see Lib) to
-- which the ali applies. But 'e' entries are really structural
-- and simply indicate where packages end. This information can
-- be used to reconstruct scope information for any entities
-- referenced from within the package. The line/column values
-- for these entries point to the semicolon ending the construct.
-- i is used to identify a reference to the entity in a generic
-- actual or in a default in a call. The node that denotes the
-- entity does not come from source, but it has the Sloc of the
-- source node that generates the implicit reference, and it is
-- useful to record this one.
-- k is used to denote a reference to the parent unit, in the
-- cross-reference line for a child unit.
-- l is used to identify the occurrence in the source of the
-- name on an end line. This is just a syntactic reference
-- which can be ignored for semantic purposes (such as call
-- graph construction). Again, in the case of an accept there
-- can be multiple l lines.
-- p is used to mark a primitive operation of the given entity.
-- For example, if we have a type Tx, and a primitive operation
-- Pq of this type, then an entry in the list of references to
-- Tx will point to the declaration of Pq. Note that this entry
-- type is unusual because it an implicit rather than explicit,
-- and the name of the refrerence does not match the name of the
-- entity for which a reference is generated. These entries are
-- generated only for entities declared in the extended main
-- source unit (main unit itself, its separate spec (if any).
-- and all subunits (considered recursively).
-- If the primitive operation overrides an inherited primitive
-- operation of the parent type, the letter 'P' is used in the
-- corresponding entry.
-- t is similar to e. It identifies the end of a corresponding
-- body (such a reference always links up with a b reference)
-- Subprogram Body end [DESIGNATOR];
-- Package Body end [[PARENT_UNIT_NAME .] IDENTIFIER];
-- Task Body end [task_IDENTIFIER];
-- Entry Body end [entry_IDENTIFIER];
-- Protected Body end [protected_IDENTIFIER]
-- Accept Statement end [entry_IDENTIFIER]];
-- Note that in the case of accept statements, there can
-- be multiple b and t entries for the same entity.
-- x is used to identify the reference as the entity from which
-- a tagged type is extended. This allows immediate access to
-- the parent of a tagged type.
-- z is used on the cross-reference line for a generic unit, to
-- mark the definition of a generic formal of the unit.
-- This entry type is similar to 'k' and 'p' in that it is an
-- implicit reference for an entity with a different name.
-- The characters >, <. =, and ^ are used on the cross-reference
-- line for a subprogram, to denote formal parameters and their
-- modes. As with the 'z' and 'p' entries, each such entry is
-- an implicit reference to an entity with a different name.
-- [..] is used for generic instantiation references. These
-- references are present only if the entity in question is
-- a generic entity, and in that case the [..] contains the
-- reference for the instantiation. In the case of nested
-- instantiations, this can be nested [...[...[...]]] etc.
-- The reference is of the form [file|line] no column is
-- present since it is assumed that only one instantiation
-- appears on a single source line. Note that the appearence
-- of file numbers in such references follows the normal
-- rules (present only if needed, and resets the current
-- file for subsequent references).
-- Examples:
-- 44B5*Flag_Type{boolean} 5r23 6m45 3|9r35 11r56
-- This line gives references for the publicly visible Boolean
-- type Flag_Type declared on line 44, column 5. There are four
-- references
-- a reference on line 5, column 23 of the current file
-- a modification on line 6, column 45 of the current file
-- a reference on line 9, column 35 of unit number 3
-- a reference on line 11, column 56 of unit number 3
-- 2U13 p3=2:35 5b13 8r4 12r13 12t15
-- This line gives references for the non-publicly visible
-- procedure p3 declared on line 2, column 13. This procedure
-- renames the procedure whose identifier reference is at
-- line 2 column 35. There are four references:
-- the corresponding body entity at line 5, column 13,
-- of the current file.
-- a reference (e.g. a call) at line 8 column 4 of the
-- of the current file.
-- the END line of the body has an explict reference to
-- the name of the procedure at line 12, column 13.
-- the body ends at line 12, column 15, just past this label.
-- 16I9*My_Type<2|4I9> 18r8
-- This line gives references for the publicly visible Integer
-- derived type My_Type declared on line 16, column 9. It also
-- gives references to the parent type declared in the unit
-- number 2 on line 4, column 9. There is one reference:
-- a reference (e.g. a variable declaration) at line 18 column
-- 4 of the current file.
-- 10I3*Genv{integer} 3|4I10[6|12]
-- This line gives a reference for the entity Genv in a generic
-- package. The reference in file 3, line 4, col 10, refers to
-- an instance of the generic where the instantiation can be
-- found in file 6 at line 12.
-- Continuation lines are used if the reference list gets too long,
-- a continuation line starts with a period, and then has references
-- continuing from the previous line. The references are sorted first
-- by unit, then by position in the source.
-- Note on handling of generic entities. The cross-reference is oriented
-- towards source references, so the entities in a generic instantiation
-- are not considered distinct from the entities in the template. All
-- definitions and references from generic instantiations are suppressed,
-- since they will be generated from the template. Any references to
-- entities in a generic instantiation from outside the instantiation
-- are considered to be references to the original template entity.
-- Cross-Reference Entity Identifiers --
-- In the cross-reference section of the ali file, entity types are
-- identified by a single letter, indicating the entity type. The
-- following table indicates the letter. A space for an entry is
-- used for entities that do not appear in the cross-reference table.
-- For objects, the character * appears in this table. In the xref
-- listing, this character is replaced by the lower case letter that
-- corresponds to the type of the object. For example, if a variable
-- is of a Float type, then, since the type is represented by an
-- upper case F, the object would be represented by a lower case f.
-- A special exception is the case of booleans, whose entities are
-- normal E_Enumeration_Type or E_Enumeration_Subtype entities, but
-- which appear as B/b in the xref lines, rather than E/e.
-- For private types, the character + appears in the table. In this
-- case the kind of the underlying type is used, if available, to
-- determine the character to use in the xref listing. The listing
-- will still include a '+' for a generic private type, for example.
-- For subprograms, the characters 'U' and 'V' appear in the table,
-- indicating procedures and functions. If the operation is abstract,
-- these letters are replaced in the xref by 'x' and 'y' respectively.
Xref_Entity_Letters : array (Entity_Kind) of Character := (
E_Void => ' ',
E_Variable => '*',
E_Component => '*',
E_Constant => '*',
E_Discriminant => '*',
E_Loop_Parameter => '*',
E_In_Parameter => '*',
E_Out_Parameter => '*',
E_In_Out_Parameter => '*',
E_Generic_In_Out_Parameter => '*',
E_Generic_In_Parameter => '*',
E_Named_Integer => 'N',
E_Named_Real => 'N',
E_Enumeration_Type => 'E', -- B for boolean
E_Enumeration_Subtype => 'E', -- B for boolean
E_Signed_Integer_Type => 'I',
E_Signed_Integer_Subtype => 'I',
E_Modular_Integer_Type => 'M',
E_Modular_Integer_Subtype => 'M',
E_Ordinary_Fixed_Point_Type => 'O',
E_Ordinary_Fixed_Point_Subtype => 'O',
E_Decimal_Fixed_Point_Type => 'D',
E_Decimal_Fixed_Point_Subtype => 'D',
E_Floating_Point_Type => 'F',
E_Floating_Point_Subtype => 'F',
E_Access_Type => 'P',
E_Access_Subtype => 'P',
E_Access_Attribute_Type => 'P',
E_Allocator_Type => ' ',
E_General_Access_Type => 'P',
E_Access_Subprogram_Type => 'P',
E_Access_Protected_Subprogram_Type => 'P',
E_Anonymous_Access_Type => ' ',
E_Array_Type => 'A',
E_Array_Subtype => 'A',
E_String_Type => 'S',
E_String_Subtype => 'S',
E_String_Literal_Subtype => ' ',
E_Class_Wide_Type => 'C',
E_Class_Wide_Subtype => 'C',
E_Record_Type => 'R',
E_Record_Subtype => 'R',
E_Record_Type_With_Private => 'R',
E_Record_Subtype_With_Private => 'R',
E_Private_Type => '+',
E_Private_Subtype => '+',
E_Limited_Private_Type => '+',
E_Limited_Private_Subtype => '+',
E_Incomplete_Type => '+',
E_Task_Type => 'T',
E_Task_Subtype => 'T',
E_Protected_Type => 'W',
E_Protected_Subtype => 'W',
E_Exception_Type => ' ',
E_Subprogram_Type => ' ',
E_Enumeration_Literal => 'n',
E_Function => 'V',
E_Operator => 'V',
E_Procedure => 'U',
E_Entry => 'Y',
E_Entry_Family => 'Y',
E_Block => 'q',
E_Entry_Index_Parameter => '*',
E_Exception => 'X',
E_Generic_Function => 'v',
E_Generic_Package => 'k',
E_Generic_Procedure => 'u',
E_Label => 'L',
E_Loop => 'l',
E_Package => 'K',
-- The following entities are not ones to which we gather
-- cross-references, since it does not make sense to do so
-- (e.g. references to a package are to the spec, not the body)
-- Indeed the occurrence of the body entity is considered to
-- be a reference to the spec entity.
E_Package_Body => ' ',
E_Protected_Object => ' ',
E_Protected_Body => ' ',
E_Task_Body => ' ',
E_Subprogram_Body => ' ');
-- The following table is for information purposes. It shows the
-- use of each character appearing as an entity type.
-- letter lower case usage UPPER CASE USAGE
-- a array object (except string) array type (except string)
-- b Boolean object Boolean type
-- c class-wide object class-wide type
-- d decimal fixed-point object decimal fixed-point type
-- e non-Boolean enumeration object non_Boolean enumeration type
-- f floating-point object floating-point type
-- g (unused) (unused)
-- h (unused) Abstract type
-- i signed integer object signed integer type
-- j (unused) (unused)
-- k generic package package
-- l label on loop label on statement
-- m modular integer object modular integer type
-- n enumeration literal named number
-- o ordinary fixed-point object ordinary fixed-point type
-- p access object access type
-- q label on block (unused)
-- r record object record type
-- s string object string type
-- t task object task type
-- u generic procedure procedure
-- v generic function or operator function or operator
-- w protected object protected type
-- x abstract procedure exception
-- y abstract function entry or entry family
-- z generic formal parameter (unused)
-- Handling of Imported Subprograms --
-- If a pragma Import or Interface applies to a subprogram, the
-- pragma is the completion of the subprogram. This is noted in
-- the ALI file by making the occurrence of the subprogram in the
-- pragma into a body reference ('b') and by including the external
-- name of the subprogram and its language, bracketed by '<' and '>'
-- in that reference. For example:
-- 3U13*elsewhere 4b<c,there>21
-- indicates that procedure elsewhere, declared at line 3, has a
-- pragma Import at line 4, that its body is in C, and that the link
-- name as given in the pragma is "there".
-- Subprograms --
procedure Generate_Definition (E : Entity_Id);
-- Records the definition of an entity
procedure Generate_Operator_Reference
(N : Node_Id;
T : Entity_Id);
-- Node N is an operator node, whose entity has been set. If this entity
-- is a user defined operator (i.e. an operator not defined in package
-- Standard), then a reference to the operator is recorded at node N.
-- T is the operand type of of the operator. A reference to the operator
-- is an implicit reference to the type, and that needs to be recorded
-- to avoid spurious warnings on unused entities, when the operator is
-- a renaming of a predefined operator.
procedure Generate_Reference
(E : Entity_Id;
N : Node_Id;
Typ : Character := 'r';
Set_Ref : Boolean := True;
Force : Boolean := False);
-- This procedure is called to record a reference. N is the location
-- of the reference and E is the referenced entity. Typ is one of:
-- 'b' body entity
-- 'c' completion of incomplete or private type (see below)
-- 'e' end of construct
-- 'i' implicit reference
-- 'l' label on end line
-- 'm' modification
-- 'p' primitive operation
-- 'r' standard reference
-- 't' end of body
-- 'x' type extension
-- ' ' dummy reference (see below)
-- Note: all references to incomplete or private types are to the
-- original (incomplete or private type) declaration. The full
-- declaration is treated as a reference with type 'c'.
-- Note: all references to packages or subprograms are to the entity
-- for the spec. The entity in the body is treated as a reference
-- with type 'b'. Similar handling for references to subprogram formals.
-- The call has no effect if N is not in the extended main source unit
-- This check is omitted for type 'e' references (where it is useful to
-- have structural scoping information for other than the main source),
-- and for 'p' (since we want to pick up inherited primitive operations
-- that are defined in other packages).
-- The call also has no effect if any of the following conditions hold:
-- cross-reference collection is disabled
-- entity does not come from source (and Force is False)
-- reference does not come from source (and Force is False)
-- the entity is not one for which xrefs are appropriate
-- the type letter is blank
-- the node N is not an identifier, defining identifier, or expanded name
-- the type is 'p' and the entity is not in the extended main source
-- If all these conditions are met, then the Is_Referenced flag of E
-- is set (unless Set_Ref is False) and a cross-reference entry is
-- recorded for later output when Output_References is called.
-- Note: the dummy space entry is for the convenience of some callers,
-- who find it easier to pass a space to suppress the entry than to do
-- a specific test. The call has no effect if the type is a space.
-- The parameter Set_Ref is normally True, and indicates that in
-- addition to generating a cross-reference, the Referenced flag
-- of the specified entity should be set. If this parameter is
-- False, then setting of the Referenced flag is inhibited.
-- The parameter Force is set to True to force a reference to be
-- generated even if Comes_From_Source is false. This is used for
-- certain implicit references, and also for end label references.
procedure Generate_Reference_To_Formals (E : Entity_Id);
-- Add a reference to the definition of each formal on the line for
-- a subprogram.
procedure Generate_Reference_To_Generic_Formals (E : Entity_Id);
-- Add a reference to the definition of each generic formal on the line
-- for a generic unit.
procedure Output_References;
-- Output references to the current ali file
procedure Initialize;
-- Initialize internal tables.
end Lib.Xref;